I have a bronco 2 that I want to mount a couple of antennas on. I want to drill 3 holes to put NMO mounts in. I want to place one antenna at the bottom of the windshield on the drivers side to match the existing am/fm radio antenna that is on the passangers side. The other two mounts will go in the roof. My question is where is the best place to put them. I am planning to use one of the three mounts for a scanner and another for a 2 meter radio. I plan on upgrading the 2 meter to a dual bander soon (2m/440). The third will be for the future.

I live out in the country and talk mainly on 2 meter repeaters that are about 25-35 miles away. I would like to leave my options open for a future radio; hf, 10 meters, 6 meters, 220 etc. I plan to use a 1/4 wave antenna cut for 146 MHz for the scanner.

This bronco has an aftermarket sunroof installed. The roof size is about 44 inches wide by 80 inches long. From the rear of the sunroof to the rear of the vehicle there is about 54 inches of metal. There is about 8 inches of metal on the front and each side of the sunroof.

My questions are...

1. What are the dimensions that would be best to locate the two holes in the roof?2. Which antenna would you put on which mount?3. I have both a 5/8 wave Larson and 1/4 wave, which would be best for the 2 meter radio?4. When I do up grade to a duel band, what antenna would you suggest?5. Do you have any other advise or tips?

This will be the first time I have drilled a hole for an antenna. Any help will be greatly appreciated. Let me thank you in advance for you time.

Scanner aerial on front wing.5/8 for 2 metres, if you have height problems see if there is a quick detatch mount available for the NMO. If you are thinking of getting a dual band V/UHF radio unless you already have VHF aerials, get a dual band aerial.As I have very little knowledge of American cars I'll leave the mounts to your fellow Americans

With any vehicle you're not intimately familiar with, you'll have to pull down at least a corner or edge of the headliner to see where the support ribs and any wiring might be. Sometimes you can just remove a dome or cargo light and get enough of a peek that way. Once you've done that, you can confidently drill your holes. Using a hole saw antenna you should be able to drill the holes and with a fish tape/wire, pull your coax through without having to remove the headliner. From your description, the antennas will end up somewhere aft of the sunroof. Maybe put three up there- left, right and center and leave yourself room for expansion later.

I'd put the antennas that matter most on the roof. If you stick to a standard mount like NMO you don't have to decide ahead of time which mount is used for what radio. You can mix and match by simply swapping the antennas around later.

As far as models of antennas, I choose durability over gain. You mention you have a Larsen 5/8 wave which I've found to be pretty durable (mine is over 25 years old) but quarter waves are virtually indestructible and the low profile will get the nod if you need to go off road or into parking structures a lot. Again, with a standard mount you can swap around and try each for a while to see which you like better. Or, keep both in the truck and exchange when needed based on the current requirement.

For a dual band antenna you can't beat the Larsen 2/70 line. If you pick the one with the air wound coil (NMO2/70B) it's both good performing and very durable. There are also some short (~16") dual band NMO antennas which can be useful if compactness is a requirement.

One way to tell, is buy a really good stud finder. Those $15 ones use capacitance to detect the stud, and they won't work. The ultrasound ones (upwards of $60) work fairly well if you know how to use one. The really good ones (upwards of $100) use RF, and they have no trouble finding the braces.

Finding the support ribs should not be a problem. I can get to to it from below. How far apart should I drill the holes? How far do I need to stay away from the edge of the roof? I thought I would drill the two holes down the center line of the roof, one right behind the sunroof and the other centered between the first and the roof edge. Does this sound OK? Am I correct that the 8" of metal around the sunroof will be OK for a groundplane?

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